A discriminated variant of the Observation type used when an observer monitors structural changes in a dataset's schema. Schema observations detect events such as added or removed columns, type changes, and renamed columns, and raise alerts based on the configured trigger rules. The observationType field must be set to SCHEMA_DRIFT to select this observation variant.
Parameters
| Property | Description |
|---|---|
alertingConfig |
The alerting configuration that defines thresholds, confidence intervals, and warning levels for this observation. The required sub-type is determined by the alertingMode field within the configuration. |
historyCount |
The number of historical data points the observation retains to establish a baseline for anomaly detection. Higher values produce more stable baselines. When omitted, the system applies a default history window. |
metricConfiguration |
A map of metric name to numeric weight or threshold value. Used to tune sensitivity for observations that support configurable metric parameters. Omit when not applicable to the observation type. |
metricsList |
The list of row-level metrics to collect for this observation. Supported values are ROW_COUNT and FILTER_COUNT. Applicable to volume-type observations. When omitted, the default metrics for the observation type are used. |
timeUnit |
The unit of time used for freshness interval calculations. Accepted values are HOURS, DAYS, and WEEKS. Required for freshness observations. Omit for observation types that do not track intervals. |
excludedColumns |
The columns to omit from metric calculations. Each entry names a column that should not contribute to the observed metric values. Omitting this list includes all columns in the observation. |
triggers |
The list of schema change triggers that activate alerts for schema drift observations. Each trigger specifies a change type and the severity of the resulting alert. Omit for observation types that do not monitor schema changes. |
observationType |
The discriminator that identifies which observation variant is active. Must match the specific type this object represents. |
JSON Example
{
"observationType": "SCHEMA_DRIFT",
"historyCount": 10,
"alertingConfig": {
"alertingMode": "THRESHOLD_ONLY"
},
"triggers": [
{ "triggerType": "COLUMN_DELETED", "severity": "ALERT", "enabled": true },
{ "triggerType": "COLUMN_ADDED", "severity": "WARN", "enabled": true }
]
}